Listen to layer (object) position

Is there any way to listen to an object position that is part of the lottie animation? I can change its position by applying a value callback to its keypath. What I need is to listen to its position without modifying it.

If not, will you handle it in future releases?

I tried to use LottieValueCallback to get the position:

lottieAnimationView.addValueCallback(
                    new KeyPath("Gift Outlines"),
                    LottieProperty.TRANSFORM_POSITION,
                    new LottieValueCallback<PointF>(){
                        @Override
                        public PointF getValue(LottieFrameInfo<PointF> frameInfo) {
                            return super.getValue(frameInfo);
                        }
                    }
            );

The problem is that super.getValue(frameInfo) always returns null. I assumed super.getValue(frameInfo) return the position of the “Gift Outlines” at the current call and it will be called each time “Gift Outlines” moves . I need t to listen to “Gift Outlines” position.

[silviugeorgian77]

This doesn’t resolve anything.

You don’t understand the problem. Please read again what @islamassi wrote. At the moment, the so called LottieValueCallback is more of a dynamic getter than a callback. Lottie uses this getter in order to change the animated values for each frame.

We need a callback with the animated value without changing the value returned by the getter. For this, we need to use the hacks I wrote above.

If we return null in the getter, we just lose the animation. Nothing will happen.

[gpeal]

Thanks for the investigation. I’ll try to look in to this further for a future release.